> Then if we want to disprove the null hypothesis there we give one programmer brainfuck and the other Python
Hence "reasonably well supported modern general-purpose programming languages".
I think this null hypothesis is where most sufficiently jaded working programmers end up, and business leaders without a programming background will start there because it's all Greek to them. I'm not here to prove its correctness, just to raise it as a very real factor working against Haskell's adoption.
Nothing would delight me more than for somebody to come along and unequivocally prove that Haskell is a silver bullet. But the point here, really, is that nobody has yet.
I noticed that and considered (and should have said) this to prevent any miscommunication:
I feel the burden of proof for the claim "language choice makes only marginal differences" is one that is very high and one you have not met.
Then if we want to disprove the null hypothesis there we give one programmer brainfuck and the other Python ;)